Enter a value in any field to convert between all units
Visual representation of inductance magnitude
Note: The inductor shows relative size based on inductance value.
Calculate inductance for different coil types
When selecting an inductor for your design, consider these important factors:
Understanding inductance in various fields and industries
In power electronics, inductors are critical components in:
The inductor in a switching converter stores energy during the switch-on period and releases it during the switch-off period, maintaining current flow to the load.
RF applications use inductors for:
In RF design, the self-resonant frequency (SRF) of the inductor is critical - it must be well above the operating frequency.
Power systems use large inductors for:
Modern vehicles use inductors in:
Automotive-grade inductors must withstand harsh environments, temperature extremes, and vibration.
Inductance is a property of an electrical conductor by which a change in current through it induces an electromotive force (EMF) in both the conductor itself and in any nearby conductors.
The SI unit of inductance is the henry (H), named after Joseph Henry. For practical applications, we use various multiples and submultiples of the henry:
Inductance values map closely onto frequency: the higher the frequency, the smaller the inductance that matters.
The practical consequence of the nanohenry end is worth stating plainly: a 10 nH stray inductance carrying a current changing at 100 A/µs develops v = L di/dt = 1 V. Multiply that by the switching speeds of modern wide-bandgap devices and layout stops being cosmetic.
| Prefix | Symbol | Factor |
|---|---|---|
| pico | p | 10−12 |
| nano | n | 10−9 |
| micro | µ | 10−6 |
| milli | m | 10−3 |
| kilo | k | 103 |
| mega | M | 106 |
| giga | G | 109 |
Two conventions cause real errors. Case matters: m is milli and M is mega, a factor of a billion apart, so writing mW when MW is meant is not a typo anyone can shrug off. And µ is frequently written as u because it is easier to type — 10uF and 10µF mean the same thing, and the substitution is universal enough in datasheets and schematics to be treated as standard.
Engineering notation — exponents restricted to multiples of three — exists precisely so that every value maps onto a prefix. It is why components are specified as 4.7 kΩ rather than 0.0047 MΩ, and why keeping values in that form makes mental arithmetic and cross-checking far easier.
Roughly 1 nH per millimetre of length, varying with width and proximity to a return plane. It is negligible at mains frequency but dominant at switching edges.
Because v = L di/dt. Even 10 nH develops a volt when current changes at 100 A/µs, and fast switching devices routinely exceed that rate.
m is milli, meaning one thousandth, and M is mega, meaning one million. They differ by a factor of a billion, so case must be written carefully.
Because µ is awkward to type on many keyboards and did not survive older character encodings. Writing 10uF for 10µF is standard practice in datasheets and schematics.
Scientific notation restricted to exponents that are multiples of three, so that every value corresponds to an SI prefix. It is why components are quoted as 4.7 kΩ rather than 0.0047 MΩ.